I think my frame is sagging a little also... however, mine is a furniture problem; my chest has fallen toward my drawers!
OK, I'll get serious now!
I can't say that I envy you but you will probably have a very good job when itís completed! You will have learned a lot and you will at least know just how solid every thing is after it's finished.
Thereís just something about doing it your self that gives a satisfaction of knowing that itís been done right!
Looking forward to seeing the pictures!